The invention relates to an apparatus for transporting material webs, especially webs of packaging material, having lateral recesses and/or orifices and/or projections arranged at regular distances from one another, by means of endless conveyors, especially by means of at least one conveying drum, the material web bearing on the endless conveyor during transport.
The exact precisely positioned transport of material webs is especially important in packaging technology when the material web serves for the production of blanks. The blanks are conventionally provided with a print, by means of which the exact separation of the blanks from the material web is brought about. With material webs made of paper, these are provided, for the exact control of conveying and driving members, with print marks which are sensed by stationary print-mark readers.
The invention is concerned with the transport of material webs made especially of thin cardboard for the production of corresponding blanks, primarily for hinge-lid packs for receiving cigarettes. The blanks for this type of pack have throughout the world a characteristic construction with a special shaping in the end regions of the elongate blanks. The special design characteristic stems, on the one hand, from a projection arranged at the end on the lid side and intended for a lid inner tab and, on the other hand, from oblique faces in the region of lateral folding tabs (side tabs). When material webs having blanks oriented transversely to the longitudinal direction of these are formed from a blank of this type, projections and depressions are obtained at the edges. One example of such a material web is the subject of U.S. Pat. No. 4,898,569. In this example, the blanks within the material web are prepunched not only at the longitudinal edges of the latter, but also in the transverse direction by making the punchings, conventional in a hinge-lid pack, for the lateral folding tabs. Furthermore, the connection between adjacent blanks within the material web is designed so that only residual connections, namely small severable or tear-off material webs, remain.